/*
 * Copyright 2017 HugeGraph Authors
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with this
 * work for additional information regarding copyright ownership. The ASF
 * licenses this file to You under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */

package com.baidu.hugegraph.api.filter;

import java.io.IOException;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.zip.GZIPInputStream;

import javax.inject.Singleton;
import javax.ws.rs.NameBinding;
import javax.ws.rs.ext.Provider;
import javax.ws.rs.ext.ReaderInterceptor;
import javax.ws.rs.ext.ReaderInterceptorContext;

@Provider
@Singleton
@DecompressInterceptor.Decompress
public class DecompressInterceptor implements ReaderInterceptor {

    public static final String GZIP = "gzip";

    @Override
    public Object aroundReadFrom(ReaderInterceptorContext context)
                                 throws IOException {
        // NOTE: Currently we just support GZIP
        String encoding = context.getHeaders().getFirst("Content-Encoding");
        if (!GZIP.equalsIgnoreCase(encoding)) {
            return context.proceed();
        }
        context.setInputStream(new GZIPInputStream(context.getInputStream()));
        return context.proceed();
    }


    @NameBinding
    @Retention(RetentionPolicy.RUNTIME)
    public @interface Decompress {
        String value() default GZIP;
    }
}
